Nevermind, i'll post my last test with separated engine
So first, electric patches activated or not, i have the same issue
Surfaced or not, it's the same too.
Then, only my right propeller is working correctly!
BUT rpm gauge is inversed
I have right propeller engaged, and it's left rpm gauge working (the red one).
Each time i activate left propeller (the green rpm gauge is working!), but my speed cursor is not responding at all (as well as big knukle gauge in main room), even though the speed is well running...and left propeller turning.
Also, i can't stop speed. I have to engage both propellers, then order whatever speed, then clic on 0 to make it respond again.
Note that with both prop submerged at very slow speed ahead, i'm running 1.5 knot at 800 rpm both gauges...while with only one prop engaged, speed drop to 1.1 knot and still 800 rpm on one gauge.
Interesting for the least, if i COULD BE SURE noise signal dropped as well, so destroyers have more difficulties to hear me!
Otherwise, completely useless imo...
Would be interesting to test if destroyers have more difficulty to find us running only one propeller...